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Abstract: Differential cross sections from fully microscopic calculations of inelastic proton scattering off 208Pb are compared to experimental scattering data for incident proton energies between 65 and 201 MeV. The required nucleon–nucleus interactions were formed by folding nuclear structure information with a reliable nucleon–nucleon effective interaction that has no adjustable parameter. The absence of phenomenological normalisation in our approach offers the possibility to interpret with confidence the calculated results in terms of the quality of the underlying nuclear structure description: a feature that had been reserved, until recently, to the electron probe. We have used this method to investigate the effect of long range correlations embedded in excited states on calculated inelastic observables and demonstrate the sensitivity of nucleon scattering predictions to details of the nuclear structure. [Copyright &y& Elsevier]

We have surveyed known threshold excitations of mirror systems seeking systematic trends to predict masses of nuclear systems that are unmeasured. For the same purpose, we review mass equations for the ground states of isobaric multiplets. We use both methods to estimate the mass of the unmeasured 17Na ground state, as well as its energy gap to the p + 16Ne threshold. The results are discussed and compared to calculations performed recently in model-dependent studies. [ABSTRACT FROM AUTHOR]

The article studies the scattering of neutrons from Ne22 with the multichannel algebraic scattering (MCAS) formalism. It also utilizes the extended form of MCAS to allow nucleon coupling of different strengths between some of the set of target states and the rotor band. It also discusses the use of simple collective-rotor prescription to model target states associated with nucleon coupling.

Abstract: The structure of 17C is used to define a nuclear interaction that, when used in a multichannel algebraic scattering theory for the system, gives a credible definition of the (compound) excitation spectra. When couplings to the low-lying collective excitations of the 16C-core are taken into account, both sub-threshold and resonant states about the threshold are found. Adding Coulomb potentials to that nuclear interaction, the method is used for the mirror system of to specify the low excitation spectrum of the particle unstable 17Na. We compare the results with those of a microscopic cluster model. A spectrum of low excitation resonant states in 17Na is found with some differences to that given by the microscopic cluster model. The calculated resonance half-widths (for proton emission) range from ∼2 to . [Copyright &y& Elsevier]

The structure of 6He is explored with proton elastic and inelastic scattering to the first 2+ excited state (Q=−1.8 MeV) of 6He in the inverse kinematics using a 24.5 A MeV 6He beam. The distorted wave approximation (DWA) with an optical potential obtained by folding an effective nucleon–nucleon (NN) g-matrix with the 6He density matrix elements as given by a large basis shell model is used to analyse the data. The comparison of predictions with the data confirms the view that 6He has an extended (halo) neutron matter distribution. [Copyright &y& Elsevier]

In a previous Letter [Phys. Rev. Lett. 96, 072502 (2006)], the multichannel algebraic scattering (MCAS) technique was used to calculate spectral properties for proton-unstable 15F and its mirror, 15C. This achieved a close match to the then-new data for p+14O elastic scattering and predicted several unusually narrow resonances at higher energies. Subsequently, such narrow resonance states were discovered. New cross section data has been published characterizing the shape of the Jπ=1/2- resonance. Herein we update that first MCAS analysis and its predictions. We also study the spectra of the set of mass-15 isobars 15C, 15N, 15O, and 15F, using the MCAS method seeking a consistent Hamiltonian for clusterization with a neutron and a proton, separately, coupled to core nuclei 14C and 14O. [ABSTRACT FROM AUTHOR]

We employ a collective vibration coupled-channel model to describe the nucleon-16O cluster systems, obtaining low-excitation spectra for 17O and 17F. Bound and resonance states of the compound systems have been deduced, showing good agreement with experimental spectra. Low-energy scattering cross sections of neutrons and protons from 16O also have been calculated and the results compare well with available experimental data. [ABSTRACT FROM AUTHOR]

What effect do particle-emitting resonances have on the scattering cross section? What physical considerations are necessary when modeling these resonances? These questions are important when theoretically describing scattering experiments with radioactive ion beams which investigate the frontiers of the table of nuclides, far from stability. Herein, a novel method is developed that describes resonant nuclear scattering from which centroids and widths in the compound nucleus are obtained when one of the interacting bodies has particle unstable resonances. The method gives cross sections without unphysical behavior that is found if simple Lorentzian forms are used to describe resonant target states. The resultant cross sections differ significantly from those obtained when the states in the coupled channel calculations are taken to have zero width, and compound-system resonances are better matched to observed values. [ABSTRACT FROM AUTHOR]

Proton and neutron densities from Skyrme-Hartree-Fock calculations of a number of nuclei with masses ranging from 28 to 58 have been used to generate optical potentials for proton elastic scattering. Those potentials, generated by folding the structure functions with effective in-medium nucleon-nucleon (NN) interactions, have been used to evaluate proton total reaction cross sections; cross sections that reveal signatures of the structures.